{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,27]],"date-time":"2026-04-27T20:27:03Z","timestamp":1777321623200,"version":"3.51.4"},"reference-count":42,"publisher":"AIP Publishing","issue":"12","content-domain":{"domain":["pubs.aip.org"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2013,3,28]]},"abstract":"<jats:p>Monomers of L-alanine (ALA) were isolated in cryogenic nitrogen matrices at 14 K. Two conformers were identified for the compound trapped from the gas-phase into the solid nitrogen environment. The potential energy surface (PES) of ALA was theoretically calculated at the MP2 and QCISD levels. Twelve minima were located on this PES. Seven low-energy conformers fall within the 0\u201310\u2009kJ\u2009mol\u22121 range and should be appreciably populated in the equilibrium gas phase prior to deposition. Observation of only two forms in the matrices is explained in terms of calculated barriers to conformational rearrangements. All conformers with the O=C\u2212O\u2212H moiety in the cis orientation are separated by low barriers and collapse to the most stable form I during deposition of the matrix onto the low-temperature substrate. The second observed form II has the O=C\u2212O\u2212H group in the trans orientation. The remaining trans forms have very high relative energies (between 24 and 30 kJ mol\u22121) and are not populated. The high-energy trans form VI, that differs from I only by rotation of the OH group, was found to be separated from other conformers by barriers that are high enough to open a perspective for its stabilization in a matrix. The form VI was photoproduced in situ by narrow-band near-infrared irradiation of the samples at 6935\u20136910 cm\u22121, where the first overtone of the OH stretching vibration in form I appears. The photogenerated form VI decays in N2 matrices back to conformer I with a characteristic decay time of \u223c15 min. The mechanism of the VI \u2192 I relaxation is rationalized in terms of the proton tunneling.<\/jats:p>","DOI":"10.1063\/1.4795823","type":"journal-article","created":{"date-parts":[[2013,3,28]],"date-time":"2013-03-28T22:07:51Z","timestamp":1364508471000},"update-policy":"https:\/\/doi.org\/10.1063\/aip-crossmark-policy-page","source":"Crossref","is-referenced-by-count":52,"title":["Near-IR laser generation of a high-energy conformer of L-alanine and the mechanism of its decay in a low-temperature nitrogen matrix"],"prefix":"10.1063","volume":"138","author":[{"given":"Cl\u00e1udio M.","family":"Nunes","sequence":"first","affiliation":[{"name":"University of Coimbra 1 Department of Chemistry, , 3004-535 Coimbra, Portugal"}]},{"given":"Leszek","family":"Lapinski","sequence":"additional","affiliation":[{"name":"University of Coimbra 1 Department of Chemistry, , 3004-535 Coimbra, Portugal"},{"name":"Polish Academy of Science 2 Institute of Physics, , Al. Lotnikow 32\/46, 02-668 Warsaw, Poland"}]},{"given":"Rui","family":"Fausto","sequence":"additional","affiliation":[{"name":"University of Coimbra 1 Department of Chemistry, , 3004-535 Coimbra, Portugal"}]},{"given":"Igor","family":"Reva","sequence":"additional","affiliation":[{"name":"University of Coimbra 1 Department of Chemistry, , 3004-535 Coimbra, Portugal"}]}],"member":"317","published-online":{"date-parts":[[2013,3,28]]},"reference":[{"key":"2023072721152178700_c1","volume-title":"Fundamentals of Biochemistry: Life at the Molecular Level","year":"2008"},{"key":"2023072721152178700_c2","volume-title":"Introduction to Proteins: Structure, Function, and Motion","year":"2010"},{"key":"2023072721152178700_c3","doi-asserted-by":"publisher","first-page":"2071","DOI":"10.1021\/ja00112a022","volume":"117","year":"1995","journal-title":"J. Am. Chem. Soc."},{"key":"2023072721152178700_c4","doi-asserted-by":"publisher","first-page":"251","DOI":"10.1016\/0166-1280(94)03943-F","volume":"332","year":"1995","journal-title":"J. Mol. Struct."},{"key":"2023072721152178700_c5","doi-asserted-by":"publisher","first-page":"65","DOI":"10.1016\/0022-2860(95)09065-7","volume":"376","year":"1996","journal-title":"J. Mol. Struct."},{"key":"2023072721152178700_c6","doi-asserted-by":"publisher","first-page":"3541","DOI":"10.1021\/jp9533640","volume":"100","year":"1996","journal-title":"J. Phys. Chem."},{"key":"2023072721152178700_c7","doi-asserted-by":"publisher","first-page":"77","DOI":"10.1016\/j.theochem.2003.10.021","volume":"671","year":"2004","journal-title":"J. Mol. Struct.:THEOCHEM"},{"key":"2023072721152178700_c8","doi-asserted-by":"publisher","first-page":"1817","DOI":"10.1002\/jcc.20683","volume":"28","year":"2007","journal-title":"J. Comput. Chem."},{"key":"2023072721152178700_c9","doi-asserted-by":"publisher","first-page":"3066","DOI":"10.1021\/ct1000236","volume":"6","year":"2010","journal-title":"J. Chem. Theory Comput."},{"key":"2023072721152178700_c10","doi-asserted-by":"publisher","first-page":"12","DOI":"10.1016\/j.molstruc.2012.01.047","volume":"1014","year":"2012","journal-title":"J. Mol. Struct."},{"key":"2023072721152178700_c11","doi-asserted-by":"publisher","first-page":"9687","DOI":"10.1021\/ja00074a039","volume":"115","year":"1993","journal-title":"J. Am. Chem. Soc."},{"key":"2023072721152178700_c12","doi-asserted-by":"publisher","first-page":"4623","DOI":"10.1021\/jp973479z","volume":"102","year":"1998","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c13","doi-asserted-by":"publisher","first-page":"878","DOI":"10.1021\/jp9933119","volume":"104","year":"2000","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c14","doi-asserted-by":"publisher","first-page":"11675","DOI":"10.1021\/ja048317c","volume":"126","year":"2004","journal-title":"J. Am. Chem. Soc."},{"key":"2023072721152178700_c15","doi-asserted-by":"publisher","first-page":"1","DOI":"10.1016\/j.cplett.2007.12.069","volume":"453","year":"2008","journal-title":"Chem. Phys. Lett."},{"key":"2023072721152178700_c16","doi-asserted-by":"publisher","first-page":"314","DOI":"10.1016\/j.jms.2008.03.022","volume":"251","year":"2008","journal-title":"J. Mol. Spectrosc."},{"key":"2023072721152178700_c17","doi-asserted-by":"publisher","first-page":"5980","DOI":"10.1039\/b924029b","volume":"12","year":"2010","journal-title":"Phys. Chem. Chem. Phys."},{"key":"2023072721152178700_c18","doi-asserted-by":"publisher","first-page":"7004","DOI":"10.1021\/jp3023716","volume":"116","year":"2012","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c19","year":"2009"},{"key":"2023072721152178700_c20"},{"key":"2023072721152178700_c21","doi-asserted-by":"publisher","first-page":"304","DOI":"10.1016\/0022-2860(71)87090-4","volume":"10","year":"1971","journal-title":"J. Mol. Struct."},{"key":"2023072721152178700_c22","doi-asserted-by":"publisher","first-page":"43","DOI":"10.1016\/j.vibspec.2008.04.012","volume":"49","year":"2009","journal-title":"Vib. Spectrosc."},{"key":"2023072721152178700_c23","doi-asserted-by":"publisher","first-page":"2550","DOI":"10.1021\/ja00504a009","volume":"101","year":"1979","journal-title":"J. Am. Chem. Soc."},{"key":"2023072721152178700_c24","doi-asserted-by":"publisher","first-page":"631","DOI":"10.1016\/S0009-2614(03)00782-6","volume":"374","year":"2003","journal-title":"Chem. Phys. Lett."},{"key":"2023072721152178700_c25","doi-asserted-by":"publisher","first-page":"126","DOI":"10.1016\/j.cplett.2005.02.067","volume":"406","year":"2005","journal-title":"Chem. Phys. Lett."},{"key":"2023072721152178700_c26","doi-asserted-by":"publisher","first-page":"5339","DOI":"10.1039\/b610962d","volume":"8","year":"2006","journal-title":"Phys. Chem. Chem. Phys."},{"key":"2023072721152178700_c27","doi-asserted-by":"publisher","first-page":"7499","DOI":"10.1021\/jp900771g","volume":"113","year":"2009","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c28","doi-asserted-by":"publisher","first-page":"11715","DOI":"10.1021\/ja972362l","volume":"119","year":"1997","journal-title":"J. Am. Chem. Soc."},{"key":"2023072721152178700_c29","doi-asserted-by":"publisher","first-page":"16188","DOI":"10.1021\/ja038341a","volume":"125","year":"2003","journal-title":"J. Am. Chem. Soc."},{"key":"2023072721152178700_c30","doi-asserted-by":"publisher","first-page":"144507","DOI":"10.1063\/1.3484943","volume":"133","year":"2010","journal-title":"J. Chem. Phys."},{"key":"2023072721152178700_c31","doi-asserted-by":"publisher","first-page":"10539","DOI":"10.1021\/jp3076436","volume":"116","year":"2012","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c32","doi-asserted-by":"publisher","first-page":"391","DOI":"10.1080\/01442350701371919","volume":"26","year":"2007","journal-title":"Int. Rev. Phys. Chem."},{"key":"2023072721152178700_c33","doi-asserted-by":"publisher","first-page":"6725","DOI":"10.1021\/jp801151k","volume":"112","year":"2008","journal-title":"J. Phys. Chem. B"},{"key":"2023072721152178700_c34","doi-asserted-by":"publisher","first-page":"064511","DOI":"10.1063\/1.3683217","volume":"136","year":"2012","journal-title":"J. Chem. Phys."},{"key":"2023072721152178700_c35","doi-asserted-by":"publisher","first-page":"9095","DOI":"10.1063\/1.1521429","volume":"117","year":"2002","journal-title":"J. Chem. Phys."},{"key":"2023072721152178700_c36","doi-asserted-by":"publisher","first-page":"1331","DOI":"10.1063\/1.1760733","volume":"121","year":"2004","journal-title":"J. Chem. Phys."},{"key":"2023072721152178700_c37","doi-asserted-by":"publisher","first-page":"3617","DOI":"10.1021\/jp044070u","volume":"109","year":"2005","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c38","doi-asserted-by":"publisher","first-page":"4823","DOI":"10.1021\/jp212597y","volume":"116","year":"2012","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c39","doi-asserted-by":"publisher","first-page":"15902","DOI":"10.1021\/ja107531y","volume":"132","year":"2010","journal-title":"J. Am. Chem. Soc."},{"key":"2023072721152178700_c40","doi-asserted-by":"publisher","first-page":"7041","DOI":"10.1021\/jp0717600","volume":"111","year":"2007","journal-title":"J. Phys. Chem. A"},{"key":"2023072721152178700_c41","doi-asserted-by":"publisher","first-page":"906","DOI":"10.1038\/nature07010","volume":"453","year":"2008","journal-title":"Nature (London)"},{"key":"2023072721152178700_c42","unstructured":"See supplementary material at http:\/\/dx.doi.org\/10.1063\/1.4795823 for: Table S1. Internal coordinates used in the normal modes analysis for conformers of ALA; Table S2. Experimental FTIR spectrum, calculated and vibrational assignments for ALA conformer I; Table S3. Experimental FTIR spectrum, calculated and vibrational assignments for ALA conformer IIa; Tables S4 and S5. Data of the evolution of ALA conformers VI and I, immediately after the irradiation of the O\u2212H overtone of conformer I; Fig. S1. Graphical representation of ALA conformers; Fig. S2. Relaxed one-dimensional potential energy profiles calculated for ALA, at the MP2\/6-311++G(d,p) and QCISD\/6-311++G(d,p) levels, in the vicinity of structure II; Fig. S3. Experimental IR spectrum of monomeric ALA isolated in a nitrogen matrix at 14 K compared with the spectrum obtained after irradiation with \u03bb = 6935 cm\u22121 and with the simulated spectrum of conformer IIa at the B3LYP\/aug-cc-pVTZ level; Cartesian coordinates, vibrational frequencies, and infrared intensities for of all minimum-energy structures of ALA calculated at MP2\/6-311++G(d,p), B3LYP\/aug-cc-pVTZ, and QCISD\/6-311++G(d,p) levels."}],"container-title":["The Journal of Chemical Physics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.aip.org\/aip\/jcp\/article-pdf\/doi\/10.1063\/1.4795823\/15462747\/125101_1_online.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"syndication"},{"URL":"https:\/\/pubs.aip.org\/aip\/jcp\/article-pdf\/doi\/10.1063\/1.4795823\/15462747\/125101_1_online.pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,7,27]],"date-time":"2023-07-27T21:15:35Z","timestamp":1690492535000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.aip.org\/jcp\/article\/138\/12\/125101\/844519\/Near-IR-laser-generation-of-a-high-energy"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2013,3,28]]},"references-count":42,"journal-issue":{"issue":"12","published-print":{"date-parts":[[2013,3,28]]}},"URL":"https:\/\/doi.org\/10.1063\/1.4795823","relation":{},"ISSN":["0021-9606","1089-7690"],"issn-type":[{"value":"0021-9606","type":"print"},{"value":"1089-7690","type":"electronic"}],"subject":[],"published-other":{"date-parts":[[2013,3,28]]},"published":{"date-parts":[[2013,3,28]]},"article-number":"125101"}}